In numerous yarn treatments and in the machines employed to manufacture textile products it is usual to bear a multiplicity of yarn bobbins or reels on a rack structure, commonly called creel. The creel is adjacent to the textile machine to be fed, but at a short distance from it. It is also usual to lead the yarns of the twisting bobbins or reels to the textile machine both through thread guide eyes and through continuous tubular guides.
When yarns are taken and unwound by twisting bobbins or reels, they show a remarkable tendency to release fly and some lint which is undesirable for a lot of reasons. Fly and lint tend to contaminate the atmosphere and represent a significant risk for the health of the operators employed on machines.
In addition, fly may have a negative influence on textile machines and cause considerable accumulations which may affect the correct operation of textile machines or penetrate into the fabric during manufacture thus giving rise to fabric defects.
Therefore, it is necessary and convenient to remove fly and lint from the atmosphere in which the yarns to be fed to the textile machine are present.
An attempt in this way was proposed in GB-A-2,087,543. This present publication proposes to remove any lint from yarns by blowing a current of air on the yarns themselves and by placing a filtering shield into the creel. However, such an execution involves some disadvantages as it requires a substantially closed environment for yarn twisting bobbins or reels. Consequently, the air to be blown on the yarns must be controlled and directed to the filter. Furthermore, the operation in a closed environment is often unsatisfactory as the casing defining the environment represents an obstacle for access and easy replacement of yarn twisting bobbins. In addition, the filtering shield needs a regular cleaning. The presence of a casing makes cleaning difficult, too. Furthermore, the cleaning of the filtering shield implies a waste of time and productivity as the machine cannot work during cleaning operations, with a considerable drop in its performances. On the other hand, if the filter is not clean, the whole installation becomes inefficient. The cleaning time should be eliminated by removing filters or obstructions within the creel.
The above mentioned patent publication also proposed to increase the humidity content during yarn unwinding from the twisting bobbin or reel by spraying some water by means of an atomization nozzle on the yarn itself, while it is leaving the twisting bobbin. Such humidification may reduce the ability of the yarn to carry static electricity and also reinforce yarns by slightly modifying cells and structure of fibers.
However, the present applicants have ascertained that water spraying on yarns through an atomization nozzle is an unsatisfactory and inefficient method to increase the humidity content of yarns themselves. As a matter of fact, it ensures a poor control of the humidity content of yarns, and the filtering shield gets obstructed even more rapidly because of humidity and wet fly.
In practice, along with all previous attempts to remove fly from yarns and increase the yarn humidity content, the adoption of a casing around the whole creel structure is an essential element of the above mentioned patent publication.
Other documents, such as EP-0,335,230, DE-3,833,434 and U.S. Pat. No. 4,784,349, refer to a creel with a fly removal system also with closed structure. The document EP-0,305,818 describes a creel with partially open structure, while further documents, such as EP-0,160,231 and U.S. Pat. No. 4,948,067, refer to creels with open construction with air circulation, with or without filtering shield. Therefore, it is evident that the well-known constructions are unsatisfactory for a lot of aspects. In fact:
they have difficult access for operators when their structure is closed; PA0 they may be harmful to the operator's health, as some creel constructions blow the lint into work environments; PA0 they are inefficient, as the filtering shield, when present, gets obstructed rapidly; PA0 they are not very economical, as the time required to clean filters can also exceed 10% of the working time of a machine, even more in presence of singed yarns; PA0 in some cases, their operation is complicated, e.g., it is necessary to have the yarn ends passed behind the standards supporting bobbins; PA0 the creels equipped with a device to increase air humidity content around twisting bobbins or reels can only be controlled with difficulty and tend to get obstructed or to have an excess flow.